The present invention relates to a method and a system for creating Call Detail Records databases (CDRs) in management systems of modern telecommunications networks. There is a co-pending US patent application claiming priority from an Israeli patent application No. 130894 filed Jul. 12, 1999.
Collecting information on calls in real time and building the so-called CDRs is required for the functioning of management systems in modem telecommunications networks, such as a billing management system, a fraud management system, a service management system, a quality of service management system or the like.
It is becoming more and more complicated to manage telecommunications networks in today""s communication environment due to the increasing interconnectivity between networks of different type and owing to the appearance of additional types of Network Elements (NE) providing transport bearer and signaling capabilities. The term xe2x80x9cbearerxe2x80x9d should be understood as voice, fax or data signals to be transported through the network, while the term xe2x80x9csignalingxe2x80x9d covers service information transmitted in so-called signaling networks for proper handling the appropriate bearer.
A single call instance (voice, fax, etc.) may span a number of various networks and be handled by several types of Network Elements, as well as the signaling data on the call can be delivered via several different signaling protocols (e.g., an Intelligent Network call, a GSM call, etc.).
The management systems presently in use incorporate CDRs built in such a way that one source of information (say, a particular Network Element or a particular signaling system) is used for creating one CDR data base.
U.S. Pat. No. 5,606,600 describes processing of data, incorporated in call detail records (CDR) obtained from network switches, by a statistics engine. A so-called network information concentrator is introduced which collects, at a single point, call records from various network elements. This enables the concentrator to create data buffers of CDRs that are input to the statistics engine for processing. It is not described, however, how the call records are collected from different network elements, which information sources are used and how the data is integrated.
U.S. Pat. No. 5,008,929 describes a billing system for use in a telephone signaling network. The network includes signal transfer points (STPs) for receiving and routing message signaling units (MSUs), and a plurality of service control points (SCPs) linked to corresponding STPs. Each SCP comprises a database that includes call data provided by one or more of telephone companies participating in the network. The billing system comprises means for capturing at least a portion of the MSUs received by one or more STPs and processes thereof to produce usage data that indicates service recipients and service providers. The described system, however, concerns only the signaling information in the signaling network and is intended for billing only. The description fails to explain how data bases of different SCPs are integrated (combined).
It is therefore the object of the present invention to provide a novel method and an appropriate system for building CDR data bases useful for management systems in telecommunications networks.
The above object can be achieved by providing a method for building an Integrated Call Detail Records data base in a telecommunications network in real time, comprising steps of:
collecting input information concerning a particular call from two or more data sources, said input information comprising call related events;
merging said call related events and recording the merged events concerning the particular call in real time, thereby forming the real time Integrated Call Detail Records data base.
The Integrated Call Detail Records data base (Integrated CDR) should be understood as a CDR data base of a high level management system in a telecommunication network, such as a Billing Collector, a Billing System, a Fraud Management System, a System for Quality of Service Management, and especially those managing combined networks which comprise different domains such as PSTN (plane service telephone network), Voice over IP and/or others. The high level management systems of interest are those operating with information layers which cannot be obtained at one source and usually,xe2x80x94even at one network domain of a combined network.
In accordance with one particular version of the method, all said data sources are sources of signaling data.
Such management systems as a Network Management center, applications of signaling system SS7, Billing Collector or other Billing assistance systems, Roaming manager can use Integrated CDRs built using sources of signaling data only. For example, an Integrated CDRs of a Billing assistance system may incorporate data on pre-paid calls for a particular customer and provide real-time update of the remaining credit by registering signaling data on calls which the customer effects over each and every part of the network of interest.
Alternatively, the method may be accomplished if at least one of said data sources is a bearer (such as voice, fax or data), and at least one of said data sources is a source of signaling data associated with said bearer. It should be understood that the data source being a bearer is actually a source of call related events extractable from the bearer, e.g., the bearer classification, DTMF, any Quality of Service parameters, etc.
According to a preferred version of the method, said at least two sources of information are situated at different Interface Points of the communication network, said interface points being understood as located on links connecting network elements (NE) to one another.
Depending on the kind of network and its elements, the link, may carry a bearer (e.g., voice, fax, data), a combination of a bearer and in-band signaling, or out-of-band signaling.
For example, said at least two data sources may comprise a bearer signal and a signaling data, for example both originating from a communication link carrying both the bearer and its in-band signaling. However, the two data sources may comprise a bearer signal and a signaling data which is obtained from any appropriate in-band or out-of band signaling source.
In the version of the method, where the two data sources are both signaling data sources, they might constitute:
an in-band signaling (taking place over a communication link serving for transmitting the bearer), and an out-of-band signaling, for example created by a signaling network SS#7;
both signaling sources may be out-of-band signaling sources with different protocols,
both signaling sources may be in-band signaling from different interface points.
It should be noted, that the telecommunications network may comprise a number of component networks, such as a Telephony Network, an Access Network and an IP Network. The mentioned sources of information may therefore be situated at different said component networks, i.e., at a number of Interface Points distributed in more than one said component networks.
The method can preferably be performed by utilizing at least one probe (such as Front End System FES probe) capable of non-intrusive collecting said input information from at least one data source, but preferably from two or more data sources, and a computerized means comprising a Central Computer (CC) connected to said FES and provided with appropriate hardware and software modules.
In the described method, the step of collecting the input information preferably comprises picking out the call related events (so-called Pre-CDRs) therefrom. The picking out can be accomplished as follows:
processing the input information by a plurality of Interface Handlers (IH), capable of handling a variety of interfaces mapped to different links in the telecommunications network (which, in turn, may include a number of component networks and signaling networks);
applying a plurality of Protocol Parsers (PP) capable of handling a variety of protocols, wherein each said Protocol Parser handles a single protocol type.
Optionally, the method may comprise a step of storing the separated call related events (Pre-CDRs) for further processing.
In view of the above, the method can be accomplished in the following order:
collecting said input information by each of the probes,
picking out call related events (or Pre-CDR events) by performing initial processing of the collected input information using said IH and PP;
merging said call related events by said computerized means and recording the merged call related events in the Integrated CDR data base with respect to a particular call.
Preferably, the step of merging and recording is performed in two stages:
a) forming one or more CDR databases, using for each of said CDR databases the call related events (so-called Pre-CDR events) associated with one telecommunications protocol,
b) forming an Integrated CDR from said one or more CDRs obtained at step (a) and all remaining call related events (Pre-CDR events) associated with the same particular call.
Finally, steps (a) and (b) in the above-mentioned version of the method can be performed by generating said CDRs and Integrated CDRs from said Pre-CDRs by a CDR builder, based on pre-defined rules; said rules being stored in correlation tables in the memory of the computerized means.
The rules indicate to the CDR Builder which events should be introduced into the final Integrated CDR and determine the association or linkage between different call events. Such associations may include one or more of the following parameters related to a call: origin and destination identifications mapped to a relevant communication/application layer, time stamp, link/trunk ID, bearer type, and other identities.
According to a second aspect of the invention, there is provided a system for building an Integrated Call Detail Records data base in a telecommunications network in real time, comprising
at least one probe capable of collecting input information, concerning a particular call, from two or more data sources and capable of picking out call related events from said input information;
computerized means connected to said at least one probe and adapted to merge said call related events and record the merged events concerning the particular call in real time, thereby creating the Integrated Call Detail Records data base.
According to the preferred embodiment of the system, all said data sources are sources of signaling data, handling said particular call.
In an alternative embodiment, at least one of said data sources is a bearer (such as voice, fax or data), and at least one of said data sources is a source of signaling data (in-band or out-of band) associated with said call.
The mentioned at least two sources of information may be situated at different Interface Points of the communication network, i.e. on links connecting network elements (NE) to one another. Depending on the kind of network and its elements, the link may carry a bearer (e.g., voice, fax, data), a combination of bearer and in-band signaling, or out-of-band signaling.
It should be noted, that the telecommunications network may comprise a number of component networks, such as a Telephony Network, an Access Network and an IP Network. The mentioned sources of information may therefore be situated at different said component networks, i.e., at a number of Interface Points distributed in more than one said component networks.
According to the most preferred embodiment of the system, said probe is a Front End System (FES) probe capable of non-intrusive collecting said input information from at least one data source, but preferably from two or more data sources. It is therefore understood, that the system may comprise more than one said probes.
The above-mentioned probes are preferably similar to the Front End System probes TRP-360 of ECTel(copyright) Ltd., Israel.
Each of the FES Probes is adapted to collect the input information (signaling and/or bearer), and to perform initial processing of this information for picking out so-called call related events (or Pre-CDR events) which are entered to the computerized means for further processing. The computerized means may comprise a Central Computer (CC) connected to said one or more FES probes. The CC in cooperation with said FES Probes is capable of merging said call related events and recording thereof in the integrated CDR data base with respect to particular calls.
Preferably, the Central Computer is operative to effect a two-step processing of the call related events (Pre-CDRs) received from the Front End System Probes:
a) forming one or more CDR databases, using for each of said CDR databases the call related events (so-called Pre-CDR events) associated with one telecommunications protocol,
b) forming an Integrated CDR from said one or more CDRs obtained at step (a) and all remaining call related events (Pre-CDR events) associated with the same particular call.
According to one particular embodiment of the system, the computer means comprising the central computer CC cooperating with the FES probes includes a processor and a memory means provided with the following hardware and software modules (which can be distributed in any selected manner between said FES probes and the CC):
a plurality of Interface Handlers (IH), capable of handling a variety of interfaces mapped to different links in the telecommunications network (which, in turn, may include a number of component networks);
a plurality of Protocol Parsers (PP) capable of processing a variety of signaling protocols interfaced by the Front End System Probes, wherein each said Protocol Parser handles a single protocol type;
said IH and PP being capable of processing the input information obtained form one or more Interface Points and producing comprehensive Pre-CDRs (said call related events) which might be stored for a later processing;
a CDR builder provided with correlation tables and capable of generating CDRs and Integrated CDRs from said Pre-CDRs, based on pre-defined rules stored in the correlation tables.
The rules indicate to the CDR Builder which events should be introduced into the final Integrated CDR.
The pre-defined rules determine the association or linkage between different call events. Such associations include one or more of the following parameters related to a call: origin and destination ID/numbers, time stamp, link/trunk ID, bearer type, other identities.